Species of the Leskeaceae are widely distributed in temperate zones. They are usually epiphytic on tree trunks or growing on surfaces of rocks. There are different viewpoints about the family’s delimitation and its systematic positions. We basically adopted the system of Brotherus (1924) and P.-C. Chen et al. (1978). The genus Okamuraea is transferred from the Rhytidiaceae to this family. The Leskeaceae have a close affinity with the Thuidiaceae, but the species of the present family can be distinguished from the Thuidiaceae by the following features: 1) paraphyllia absent or few, unbranched, smooth; 2) leaf cells smooth or unipapillose; 3) capsules mostly erect, symmetric; 4) endostomes varying greatly among genera and cilia usually rudimentary, rarely well developed. Nine genera are recognized for the Leskeaceae in this treatment.